diff --git a/Gui/win32/dialogs.c b/Gui/win32/dialogs.c
index 084966604f..abfeedcb56 100644
--- a/Gui/win32/dialogs.c
+++ b/Gui/win32/dialogs.c
@@ -30,6 +30,7 @@
 #include "gui.h"
 #include "wincfg.h"
 #include "dialogs.h"
+#include "libvo/sub.h"
 
 WNDPROC OldUrlWndProc;
 LRESULT CALLBACK SubUrlWndProc(HWND, UINT, WPARAM, LPARAM);